You should not be ashamed. If it were about Khmer History, you (or we) should be. Nobody trains those Khmer Script to you if you do not select your that major. It's also good if you know it. From my point of view, being the new generation man in Cambodia does not require you to know all of those. You (or we) should retain what we have or what we are losing at the moment.
By studying Khmer Literature, you might know by doing some research of those old script. I guess you could do some research of those old Khmer script in Royal University of Phnom Penh (RUPP).